How to register a custom protocol in OSX?

Question

Communication protocols

I want to run scripts through an external handler (example://param -> python script.py param). Please explain how to register a handler. I read the article - https://support.shotgunsoftware.com/entries/127152... I repeated everything described, but refuses to work, I don't understand what I'm doing wrong. On a poppy, I first encountered such a need, on Windows, everything is easily registered in the registry.